The invention relates to textile conditioning compositions employing cationic textile softening agents and containing certain polymeric substances which increase the effectiveness of the cationic textile agents employed.
Textile conditioning, especially softening, compositions in the form of aqueous dispersions are well known, and are primarily intended to be added to the last rinse liquor in a conventional clothes-washing process. Most of such compositions currently on the market comprise a fairly low concentration, for instance about 3-10%, of a cationic textile softener or of a mixture of more than one, together with relatively minor amounts of emulsifiers, and with aesthetic additives such as colour and perfume. These compositions are used at quite low concentration in the treatment bath, for instance about 0.25% by weight.
The rinse liquors, even the last, after a conventional bath using an anionic surfactant-based detergent composition normally contain traces of residual anionic surfactant carried through from the wash liquor. Typically 5-20 parts per million of anionic surfactant is present in the final rinse liquor. This anionic surfactant reacts with the cationic softener component of a softening compositions, thereby reducing its performance. The use of relatively water soluble cationic surfactants to scavenge anionic has been described in U.S. Pat. No. 3,974,076, but these substances need to be used at considerable levels.
It has now been found that this scavenging function can be performed by very low levels of certain polymeric cationic salts. Furthermore some of these salts have been found to have softening properties in the presence of cationic softeners even when employed in baths which contain no anionic surfactant, and they even replace several times their own weight of conventional cationic softener without overall loss of softening performance of the composition. This enables the cost of such compositions to be reduced.
German Offeblengungsschrift No. 2,724,816 describes textile softening and ironing assistants containing cationic softeners or mixtures thereof with nonionic softeners and relatively high levels of cationic dextrin as agent providing the ironing assistant properties.
A paper by J. A. Faucher and E. D. Goddard in J. Colloid and Interface Science 55 (2) 313-319, 1976 describes a study of the effect of, inter alia, a cationic surfactant upon the sorption of cationic hydroxyalkyl cellulose on hair.